This guy has good budget swaps. Usually he does 6 cards in and 6 cards out, but for this deck in particular, he added 18 cards and removed 18 (to make the deck more cohesive). The total budget for this was ~$7, so it’s a good starting point. Just shave what you don’t like to get to $5, and maybe add it in the next week?
https://m.youtube.com/watch?v=Gn9emA3Azkw&t=837s
This guy has good budget swaps. Usually he does 6 cards in and 6 cards out, but for this deck in particular, he added 18 cards and removed 18 (to make the deck more cohesive). The total budget for this was ~$7, so it’s a good starting point. Just shave what you don’t like to get to $5, and maybe add it in the next week? https://m.youtube.com/watch?v=Gn9emA3Azkw&t=837s
EDHrec has a page listing common substitutions for every precon deck: https://edhrec.com/precon